Drop down list not binding with sqldatareader

Question

i have a form with a collection of about five drop down . i have my query as follows .

 string sql = \"SELECT a.clientID ,a.[cname],b.bid,b.[bname],c.contactID,          


        

Answer 1

Your choices are to either rerun/refill it or create separate readers or better yet fill a datatable instead and then you can reuse the datatable.

Answer 2

Reader is readonly and forward only that's why only first dropdonw get filled with data and others are empty. You can use datset or Datatable for same problem .

  SqlCommand cmd = new SqlCommand(sql, connection);
    cmd.CommandType = CommandType.Text;


    Dataset dsresult = cmd.ExecuteDataset();
   If(dsResult !=null)
   {
     if(dsResult.Rows.count>0) 
    {
    drClient.Enabled = true;
    drClient.DataSource = dsResult.Tables[0] ;
    drClient.DataTextField = Convert.ToString(ds.Tables[0].Columns["cname"]);
    drClient.DataValueField = ds.Tables[0].Columns["clientID"] ;
    drClient.DataBind();

    }

   }  

Datareader is connected architecture needs continuous connection and fetches one row at a time in forward mode better use dataset which uses disconnected architecture and can be used for retrieving data multiple times.

Answer 3

This seems clear postback problem.

Bind your drop down on !postback.

Eg.

if(!IsPostBack)    
 {
   populateDdl();
 }

Answer 4

Either you will have to make a seperate reader for each binding

or you can do this by filling a datatable ( i would prefer this). Like,

DataTable dt = new DataTable();
using (SqlDataAdapter a = new SqlDataAdapter(sql, connection))
{       
   a.Fill(dt);
}
drClient.DataSource = dt;
drClient.DataBind();
drBranch.DataSource = dt;
drBranch.DataBind();
drContact.DataSource = dt;
drContact.DataBind();
drFax.DataSource = dt;
drFax.DataBind();